The present invention relates to recreational trampolines, and in particular trampolines having an inflated base so they are capable of floating on water.
Water trampoline devices are well known in the art. Examples of such water trampolines are shown in U.S. Pat. No. 4,576,375 to Roberts; U.S. Pat. No. 5,810,695 to Sass; and U.S. Pat. No. 7,150,699 to Roth, among others.
Typically, the devices include an inflatable tube in the shape of a ring or doughnut, but other variations include square or rectangular shapes. The device also includes a central rebounding or bed portion, which is typically a tightly woven mesh, and is connected around its outer periphery to the inflatable tube, typically near the top of the tube. This bed portion extends over the central opening of the tube wherein the mesh or a comparable elastic surface member forms the rebound member. Various securing/attaching elements are known to connect the rebound member and the tube, including rubber strands, such as shown in the '375 patent, or more typically, springs or bungee-type devices, such as shown in the '695 patent and in U.S. Pat. No. 5,385,518 to Turner. Generally, those devices having metal springs have a greater efficiency in absorbing and returning the energy of a jumper, and thus provide a higher performance bounce. The device is commonly referred to as a water trampoline because the inflatable tube can float on water, but may also be used on land if so desired.
However, such water trampolines are still inferior in rebounding efficiency to larger trampolines that are extended off the ground by a heavy metal frame.
It is therefore a first object of the present invention to provide a water trampoline of superior rebounding efficiency.